Fig. 1: Schematic overview of the three stages of active cell competition.
From: Cell competition in primary and metastatic colorectal cancer
Cells acquire genetic alterations affecting their fitness levels. Relatively fitter cells become “winners” that actively force elimination of less fit cells (“losers”). I Induction of competition through mutations that can lead to differential uptake of beneficial factors from cells, mutations that can result in disparities of growth rates among cells and loss of apico-basal polarity that can compromise cell function and survival. II Cells sense differences in cellular fitness of their neighbors through several distinct mechanisms, such as direct cell-to-cell interactions, soluble factors released from “winner” cells and, the ability of cells to sense the mechanical pressure, under overcrowding conditions. III Pathways involved in the execution of cell competition. “Loser” cells can be either actively eliminated via apoptosis, forced to differentiation or extrusion from the epithelium.
